Four Zn II /Cd II coordination polymers (CPs) based on 2-(4carboxy-phenyl)imidazo[4,5-f]-1,10-phenanthroline (HNCP) and different derivatives of 5-R-1,3-benzenedicarboxylate (5-R-1,3-3), and {[Zn(HNCP)(5-OH-1,3-BDC)(H 2 O)·H 2 O} n (4) were synthesized under hydrothermal conditions. Compounds 1-4 were determined by elemental analyses, IR spectroscopy, and single-crystal and powder X-ray diffraction. Compounds 1 and 2 are isomorphous, presenting a 4-connected uninodal (4,4)-sql 2D framework with threefold